000
FXUS63 KAPX 221041
AFDAPX
Area Forecast Discussion
National Weather Service Gaylord MI
641 AM EDT Tue May 22 2018
.NEAR TERM...(Today through Tonight)
Issued at 244 AM EDT Tue May 22 2018
Impactful weather: Patchy (dense?) for tonight.
Pattern synopsis and forecast:
A general westerly weak flow aloft was seen across the Great Lakes
early this morning, with a shallow positively tilted shortwave in
the western portions of the Lakes. Plenty of mid and upper level
moisture was seen ahead of the wave, while southerly winds just off
the sfc have advected a more moist air mass back into a relatively
shallow cooler air mass within general high pressure in much of
lower Michigan and Wisconsin. This air mass was north of a weak sfc
low pressure currently in nrn Illinois, which was lifting ENE over
the last several hours. The combination of this moisture advection
with weak DPVA and even weaker lift over a frontal zone extending
east of the sfc low, has resulted in some periodic light rains and
developing lower clouds across nrn lower Michigan. Eastern upper
Michigan was remaining in a much drier low level air mass and only
some higher level clouds passing by. Temperatures were largely in
the upper 40s to lower 50s.
The shortwave and sfc low will cross srn lower Michigan through the
day. This will continue to spread the deeper low level moisture
across the srn half of the CWA in nrn lower. The weak forcing
resulting in the light rains will depart NE lower shortly after
sunrise, but spotty drizzle may still be possible a few hours
afterwards. Drier air from the N/NW will then gradually spread
itself southeastward through the remainder of the day and night.
This will decrease cloudiness with time. Eastern upper is likely to
be mainly sunny this afternoon, with that clearing moving through
nrn lower later this afternoon into this evening. Clear skies and
light winds for all areas tonight. Great radiational cooling
conditions will result. Again, the srn CWa will be last to clear
with the least amount of time to mix out the BL. Fog development
will be likely for many areas, especially low lying areas,
generally south of M-32 for the most part.
Highs in the lower 70s across eastern upper in most sunshine, to the
middle 60s S/SW CWA in longer stretch of clouds. Lows tonight lower
than MOS again, in the upper 30s to lower 40s. Many areas
nearing/exceeding 30+F T/TD spreads.
&&
.SHORT TERM...(Wednesday through Thursday)
Issued at 244 AM EDT Tue May 22 2018
...Quiet & warm midweek weather...
High Impact Weather Potential: Elevated fire danger possible;
otherwise, none.
Pattern Forecast: Upper level ridging will build into the Great
Lakes late Tuesday night with the ridge axis becoming centered atop
the forecast area late Thursday/Thursday night. An expansive area of
surface high pressure will keep northern Michigan under mostly sunny
skies and precipitation-free weather through the forecast period
before the potential for unsettled weather returns at various times
from Thursday night through the upcoming weekend.
Primary Forecast Concerns/Challenges: Fire weather concerns.
Little in the way of sensible weather is expected through the
forecast period with mostly sunny skies, light winds and warm
daytime temperatures being the rule both Wednesday and Thursday.
High temperatures are expected to range from the low 70s to low 80s
area-wide (cooler near the lake shores with falling late afternoon
temperatures in many Great Lakes collar counties as developing lake
breezes push inland).
Only real concern revolves around fire weather concerns despite
continued green-up across northern Michigan. The combination of warm
temperatures and abundant dry air overhead thanks to aforementioned
high pressure will result in elevated fire danger across parts of
the forecast area. Wednesday certainly looks like the greatest
threat for these conditions, despite light winds, as RH values
ranging from 20-35% across a good portion of northern lower MI.
.LONG TERM...(Thursday night through Monday)
Issued at 244 AM EDT Tue May 22 2018
High Impact Weather Potential: Minimal.
By Thursday night-Friday, an area of low pressure is expected to be
dropping out of Canada into the northern plains before sliding east
across the Great Lakes this weekend. With accompanying moisture
advection from the Gulf of Mexico, shower and perhaps occasional
thunderstorm chances return to the forecast as early as Thursday
night/Friday and continue at various times through at least
Sunday...if not all the way into the start of next week.
&&
.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
Issued at 639 AM EDT Tue May 22 2018
...Rising CIGS and clearing through the day with some possible fog
development tonight...
Weak low pressure crosses south of us through the day, taking any
light rains, MVFR/IFR CIGS and potential MVFR VSBYS in fog, east
this morning. Drier air then gradually filters into the region later
today and into this evening for clearing skies. Relative high
pressure will then take back over. The light winds and clear skies
has a chance to lead to fog development late tonight.
&&
.MARINE...
Issued at 244 AM EDT Tue May 22 2018
A weak pressure gradient in high pressure will hold over the region
through Thursday, resulting in little to no chances for any wind or
wave issues. The gradient does tighten later Thursday night into
Friday ahead of the next low pressure and chance for showers and
ultimately a chance for Thunderstorms.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
NEAR TERM...SMD
SHORT TERM...MG
LONG TERM...MG
AVIATION...SMD
MARINE...SMD